The four highlining daredevils who just dominated the longest slackline in Rio de Janeiro said their death-defying feats fulfill a lifelong dream.

Andy Lewis, Brian Mosbaugh, Hayley Ashburn and Scott Rogers are Americans who travel the world in pursuit of the next stunt.

"A lot of people keep telling me 'Hey, come to Brazil, you'll love it here,' and so I finally was like, 'OK, we're going to Brazil," Lewis said.

Once in Brazil, the four walked across a thin, slack, nylon line strung 3,000 feet above the ground. They were tethered by a harness tied to their waists.

"It's just about having fun. All of it, the reason why we do it, it's just fun for us," Lewis said. "It seems crazy from the outside, and maybe it is crazy to follow your dreams. But for us, highlining up there in the clouds, all the way above Rio, is just magical."

Photos from their month-long trip to Brazil showed the four daredevils performing various stunts on the line - including sitting cross-legged and even dangling upside down.

Lewis - whose highlining skills were showcased as part of Madonna's 2012 Super Bowl halftime show - said the "scariest moment" for him during the Brazil stunt was probably when he was hanging from the line by his ankle.

It takes years of training and dedication to be as accomplished as Lewis, Mosbaugh, Ashburn and Rogers.

"It's like trial and error, basically, of learning how to do this safely," Mosbaugh said.

Rogers added, laughing, "Luckily, the errors haven't been that drastic."

Ashburn said the key to the stunts is being fearless.

"If you're fearing for your life, you're out of your depth," she said.

Mosbaugh agreed.

"I think we wouldn't be doing it if we didn't feel safe doing it, to be honest," he said. "If we thought we were going to die every time we did it, it would be a terrifying experience."